1H nuclear magnetic resonance studies of sarcoplasmic oxygenation in the red cell-perfused rat heart.
1H nuclear magnetic resonance studies of sarcoplasmic oxygenation in the red cell-perfused rat heart.
复制标题
红细胞灌注大鼠心脏肌浆氧合的 1H 核磁共振研究。
DOI：
10.1016/s0006-3495(95)80395-4
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Wittenberg,BA
中科院分区：
文献类型：
--
作者：
Jelicks,LA;Wittenberg,BA
脱氧肌红蛋白的近端组氨酸 N δ H 质子经历了大的超精细位移，导致其 1H 核磁共振 (NMR) 信号出现在大约 76 ppm（35 摄氏度）处，即抗磁性谱区的低场。该质子的 1H NMR 用于监测离体灌注大鼠心脏的肌浆氧压。该方法监测整个心脏的细胞内氧合，并不能反映有限区域的氧合。当肌红蛋白被亚硝酸钠转化为三价铁形式时，脱氧肌红蛋白共振强度降低。牛脱氧血红蛋白的 α 和 β 亚基的 N δ H 质子的 1 H 共振不会干扰血液灌注大鼠心脏中肌红蛋白脱氧的测量。我们发现，在恒定功输出下，随着盐水和红细胞灌注心脏中灌注介质的氧合减少，稳态肌红蛋白脱氧逐渐（且可逆）增加。血液灌注心脏的心率增加八倍导致脱氧肌红蛋白信号强度没有变化。含肌红蛋白细胞的细胞内 PO2 在不断变化的工作状态下保持非常恒定。
The proximal histidine N delta H proton of deoxymyoglobin experiences a large hyperfine shift resulting in its 1H nuclear magnetic resonance (NMR) signal appearing at approximately 76 ppm (at 35 degrees C), downfield of the diamagnetic spectral region. 1H NMR of this proton is used to monitor sarcoplasmic oxygen pressure in isolated perfused rat heart. This method monitors intracellular oxygenation in the whole heart and does not reflect oxygenation in a limited region. The deoxymyoglobin resonance intensity is reduced upon conversion of myoglobin to the ferric form by sodium nitrite. 1H resonances of the N delta H protons of the alpha and beta subunits of bovine deoxyhemoglobin do not interfere with the measurement of myoglobin deoxygenation in blood-perfused rat heart. We find that steady-state myoglobin deoxygenation is increased progressively (and reversibly) as oxygenation of the perfusing medium is decreased in both saline and red blood cell-perfused hearts at constant work output. An eightfold increase in the heart rate of the blood-perfused heart resulted in no change in the deoxymyoglobin signal intensity. Intracellular PO2 of myoglobin-containing cells is maintained remarkably constant in changing work states.